Starter switch



Jan. 10, 1939. R. M. CRITCHFIELD ET AL 2,143,104

STARTER SWITCH Filed Jan. 8, 1936 5a |NvzNT0R 54 Robert M'L'm'Zc/EflE/d John W Lawsan the. ATTORNEYS Patented Jan. .10, 1939 UNITED STATES PATENT OFFICE STARTER SWITCH ware Application January 8, 1936, Serial No. 58,044

11 Claims.

This invention relates to starter switches of the type described and claimed in the patent to John B. Dyer No. 2,021,146, issued November 19, 1935. The Dyer patent discloses an electromagnet responsive to engine operation for moving a stationary contact away from the movable contact but in the direction of movement of the movable contact.

One object of the present invention is to provide a switch of improved and simplified construction having means which, in response to engine operation, will automatically cause the contacts to be separated and remain separated while the engine is self-operative, regardless of manipulation of the switch by the car driver.

To accomplish this object we provide generally a manually operated contact which is movable into engagement with a relatively stationary contact to close the starter circuit, and means responsive to engine operation for moving the stationary contact laterally out of the path of movement of the movable contact. The engine responsive means may be operated by engine suction as shown in the drawing or may be an electromagnet responsive to the operation of a generator which is driven by the engine which is started.

The disclosed embodiment of the invention includes a manually operated contact movable into engagement with two resilient, leaf spring contacts, and a movable member responsive to engine operation which causes the resilient contacts to be spread apart a distance greater than the width of the movable contact so that the movable contact can not engage the resilient contacts while the engine is running.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing wherein a preferred embodiment of the present invention is clearly shown.

In the drawing:

Fig. 1 is a sectional view of the switch and the suction device in their normal or inoperative position.

Fig. 2 is a view similar to Fig. 1, showing the operating member depressed and the contacts of the switch closed.

Fig. 3 is a view similar to Fig. 2 showing the relative positions of the switch contacts while the suction device is under the control of the vacuum produced by the engine.

Referring to the drawing, a starter switch is designated in its entirety by numeral III, which in the present instance comprises an upper and lower cup-shaped casing member and 2|, respectively. The member 20 is provided with a flange 22. The member 20 also insulatingly supports a pair of resilient terminals 23 provided with corrugated free ends to provide cam por- 5 tions 24 and bowed ends 25. The bowed ends 25 of the terminals are adapted to be engaged by a bridging memberor movable contact 26. The movable contact is insulatingly supported upon the lower end 21 of a tubular actuating member 28. The tubular member 28 is slidably supported by a sleeve 29 which is attached to the casing member 20. The upper end of the actuating member 28 is attached to a cup-shaped button 30.

The movable contact 26 is maintained out of engagement with the terminal ends 25 by a coil spring 3| about the sleeve 29. One end of the spring 3| bears against the button 30 while the other end bears against a plate 32. The plate 32 is secured against the outside of the housing 20 by the sleeve 29, the sleeve 29 having a reduced portion 34 which passes through aligned apertures provided by the plate 32 and the casing member 20. The reduced portion 34 is spun over against the inner wall of the casing member 20, as at 35.

As switches of this type are generally secured in position upon the floor board of an automotive vehicle the switch is secured in place by screws 36 extending from the floor board and passing through suitable apertures in the plate to receive nuts 31.

A rod 40 is provided at one end thereof with a portion 4| of reduced diameter which serves as a rivet for attaching to the rod 40, a cupshaped washer 42, a disc 43 and the central portion of a diaphragm 44 located between the washer and the disc. The other end of the rod is provided with a reduced portion 45 to provide a shoulder 46 against which is secured an insulating washer 41. This washer is adapted to be positioned above the cam portions 24 and between the terminals, as shown in Fig. 1. This positioning of the disc 41 is accomplished by the cup-shaped casing member 2|. The casing member .2l is provided with a flange 49 upon which is placed the peripheral edge of the diaphragm 43. The peripheral edge of the diaphragm is fastened between the flanges 22 and 49 respectively. The flange 22 of the casing member 20 is formed around the flange 49 as indicated by the U-shaped portion 50 continuing from the flange 22. When the diaphragm is secured between the casing members the diaphragm provides a closure for the switch casing member 20 and at the same time forms a closure for the casing member 2| to provide a suction chamber 60. When the diaphragm is secured in position the reduced portion of the rod will extend into the tubular member 28, the tubular member providing a guide for the reduced portion 45 of the rod 40 when the diaphragm is actuated in either direction.

Attached to the casing member 2| is a tubular bushing 5| having internal threads to receive a coupling 52. The bushing and the coupling form an enclosure for a relatively stiff spring 53 hearing at one end against a disc 56 having a small aperture 54a located within the coupling, the other end of the spring bears against the bottom wall of the cup-shaped washer 42 attached to the rod 40. Movement of the diaphragm is limited toward the casing member 2!, due to the fact that the cup-shaped washer is provided with an annular flange 55, which engages a spun-over portion of the bushing 5| which secures the bush ing 5| to the casing member 2!; The diaphragm is limited in its movement in the opposite direc tion due to the fact that the disc 43 engages the lower edges of insulators 59.

The suction chamber 60 formed by the casing member 2| and the diaphragm 44 is preferably connected with the intake manifold 64 of an internal combustion engine by a pipe 52 having one end thereof connected to the intake manifold and the other end suitably attached to the cow pling 52.

In operation, the switch of the present invention may be included in the starting motor circuit or any other electrical circuit which it is desired to control by suction in the intake marrifold, and as long as the engine is self-operative and the diaphragm issubjected to suction such circuit will be opened, due to the fact that the terminals 23 are moved laterally by the disc 41 and out of the path of the movable contact 26 indicated by dot-and-dash lines shown in Fig. 3. When the engine is stopped the diaphragm 46 and the disc 41 will be moved to their normal positions by the spring 53 to permit the terminals 23, by their own resiliency, to return to their normal position, as shown in Fig. 1.

By the above described arrangement and constructionof the parts, it will be noted that when the operator desires to close the starting motor circuit'the actuating member '28 is depressed. Upon depression of the actuating member the spring 3! is compressed to allow the movable contact 28 to engage the bowed ends 2d of the terminals 23, thus closing the circuit to the starting motor in. order to crank the engine; When the terminals 23 are bridged by the movable contact 26, see Fig. 2, current will flow from a battery l0 through wire H to one of the terminals 23, thence across the bridging contact 25 to theother terminal 23 and through wire 12' through the starting motor l3 and thence back to the battery via the ground connection it,

thereby causing the startingmotor to crank the engine.

The purpose of the small aperture Me of the disc 54 is to delay the actuation of the diaphragm 44 when the engine is first being turned over. The advantage of having this delayed action is that the switch would not be aiifected by transient changes of vacuum. For example, when the engine is being cranked the vacuum produced during the cranking operation might reach a high enough value to trip the switch momentarily, but due to the small aperture 54a in the washer 54, the vacuum available against the diaphragm is not suihcient to actuate the diaphragm to move the rod 45 carrying the disc 4! far enough downwardly, as viewed in the drawing, to spread the terminals apart to open the circuit, but as soon as the engine becomes self-operative the immediate increase of intake suction in the manifold 61 will suck the diaphragm 44 downwardly against the action of the spring 53. Since the rod 40 is attached to the diaphragm the rod 40 and the insulating disc 41 will also move downwardly. As the disc 41 moves downwardly with the diaphragm the peripheral edges of the disc 4'! will engage the cam portions 24 of the terminals 23 to spread the terminals laterally and out of the path or the movable contact 26, as indicated by the dot-and-dash lines, see Fig. 3, while the operator still has his foot on the actuating member, and thus avoid a waste of current. -When pressure upon the actuating member 28 is released, the actuating member28 will return to its normal position, Fig. l, by the spring 3|.

As long as the engine is self-operative the position ofthe terminals 23 will occupy the position shown in Fig. 3, thus theoperator cannot bridge the terminals 23 in case he accidentally depresses the actuating member 28 while the engine is self-operative.

When the engine is stopped and the diaphragm is not subjected to suction, the spring 53 will move the diaphragm 44, the rod 40 and the disc 43 in their unnermost positions, as shown in Fig. l.

The advantage of the present invention resides in the fact that in a device constructed according to this invention, the parts necessary, to produce an eflicient device, is reduced to a minimum as well as to provide other advantages having to do with simplification of improvements in the casing and providing a suction chamber on one side thereof; a plurality of flexible terminals insulatingly supported within the casing and disposed on the other side of the diaphragm; a movable contact; guide means carried by the diaphragm; manual operating means to actuate the movable contact over the guide means to bridge the terminals to close a circuit; an insulating member carried by the guide means and disposed between and normallyfre'e of the terminals, said member operating to spread the terminals out of the path of the movable contact to open the circuit when the diaphragm is moved in one direction by suction reated in the chamber.

Z. A suction controlled switch comprising, in combination, a casing; a diaphragm located within the casing and providing a suction chamber on one side thereof; a plurality of resilient terminals insulatingly supported within the casing and disposed on the other side of the diaphragm; a plunger slidable in one wall oi the casing; a bridging member secured to the inner end of the plunger and normally held out of engagement with the terminals; a stem carried by the diaphragm, an insulating member carried by the stem and disposed between the terminals; spring means located within the suction chamber and bearing against the diaphragm and adapted to normally hold the insulating member tree of the terminals; and manual means for moving the plunger and bridging member over the stem in engagement with the terminal to close a circuit to operate an apparatus whereby a change of pressure in the suction chamber will'cause the diaphragm to move against the tension of the spring and cause the insulating member to spread the terminals out of engagement with the bridging member to open the circuit so long as the diaphragm is affected by the pressure within the chamber.

3. A pressure controlled switch comprising, in combination, a casing; a pair of resilient terminals insulatingly supported on the casing; a bridging member; a tubular member slidably supported by the casing and carrying the bridging member; a diaphragm located within the casing and providing a pressure chamber on one side thereof; a rod carried by the diaphragm, said rod having a reduced portion extending into the tubular member to be guided thereby; an insulating member carried by the rod and disposed between and normally free 01' the terminals; manual means for urging the tubular member and the bridging member in one direction to make an electrical connection with the terminals to close a circuit to operate an apparatus to connect the pressure chamber with a source of fluid pressure causing the diaphragm and the insulating member to move in the same direction, said insulating member separating the terminals from and out of the path of the movablecontact to open the circuit while the diaphragm is under the influence of the fluid pressure.

4. A pressure operated switch comprising, in combination, a casing; a plurality of terminals insulatingly supported on the casing and having flexible ends; a bridging member; a diaphragm supported within the casing and providing a fluid chamber on one side thereof; a guide member for the bridging member carried by the diaphragm; manual means for moving the bridging member in one direction over the guide means and into engagement with the terminals to close a circuit; and an insulating member supported on the guide means whereby change of pressure in the fluid chamber will cause the insulating member to move in a direction to urge the ends of the terminals away from and out of the path of the bridging member to open thecircuit, and said insulating member preventing the terminals from returning to their normal position while the diaphragm is under the influence oi fluid pressure.

5. An electrical switch comprising, in combination, a cup-shaped housing; a plunger slidable in the end wall of the housing; a bridging member secured to the inner end of the plunger; terminals secured to the side walls 0! the housing and having yieldable end portions extending into the path of the bridging member; a diaphragm supported by the housing and providing a fluid pressure chamber; an insulating disc supported f1 cm the diaphragm and normally free of the yieldable end portions oi the terminals; manual means for moving the bridging member into engagement with the end portions of the terminals to close a circuit whereby a change in pressure in the chamber will cause the disc to engage and move yieldable portions clear of the bridging member and prevent engagement of said portions with the bridging member while the diaphragm is under the influence of fluid pressure.

6. A suction controlled switch comprising, in combination, a housing; a plunger slidable in one wall of the housing; a bridging member secured to the inner end oi the plunger; resilient terminals supported by the housing and located on opposite sides of the path of movement oi the bridging member; a diaphragm located within the housing and providing a pressure chamber adapted for connection with fluid pressure, an insulating member; means projecting from the diaphragm for supporting the insulating member between the terminals and normally tree 01 the terminals; and manual means for actuating the plunger to move the plunger and the bridging member in one direction to make an electrical connection with the terminals to close a circuit whereby the diaphragm may be subjected to a source 01' fluid pressure causing the diaphragm and the insulating member to be moved in the same direction, the insulating member moving the terminals away from and out ct the path of the bridging member to open the circuit, and said insulating member preventing the terminals from returning to their normal position while the diaphragm is under the influence of the fluid pressure.

'7. An electric switch comprising, in combination, a pair of flexible contacts; a movable contact having a width exceeding the normal closest spacing of the flexible contacts; manually operable means for moving the movable contact between the flexible contacts to bridge the space between them in order to complete an electrical circuit; and means for separating the flexible contacts from each other a distance greater than the width of the movable bridging contact whereby said contact is inefl'ective to bridge across the space between the flexible contacts.

8. An electric switch comprising, in combination, flexible contacts; a movable contact having a width greater than the normal closest spacing of the flexible contacts; manually operable moans formoving the movable contact into engagement with the flexible contacts to complete a circuit; and means disposed between the flexible contacts and operable thereupon to increase the distance between the flexible contacts to a distance greater than the width of the manually operated movable contact to open the circuit.

9. An electric switch comprising, in combination a plurality of flexible terminals; a movable contact; manually operable means for moving the movable contact to bridge the terminals to close a circuit; and means movable axially between the terminals for urging the flexible terminals laterally out of the path oi movement of actuated in response to fluid pressure to increase the spacing between the flexible contacts to open the circuit. said means maintaining the open circuit relation 01 the contacts while said means is under the influence of fluid pressure.

m tween the flexible contacts; and means for shifting the insulating member into engagement with the flexible contacts to separate the flexible con,- tacts 'a dis? hee greea terlthan the Width of the movablec'on t'act to op'en the circuit, said member preventing engagemen't voi the flexible contacts with the r'no vab shifted position,

FRO B BT CRITCHFIELD.

, JOHNjW-WLAWSON.

ont'a'ct while same is in the 

